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          <th colspan="3" align="center">DB_ENV-&gt;rep_set_clockskew()</th>
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            <h2 class="title" style="clear: both"><a id="repclockskew"></a>DB_ENV-&gt;rep_set_clockskew()</h2>
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      <pre class="programlisting">#include &lt;db.h&gt;

int
DB_ENV-&gt;rep_set_clockskew(DB_ENV *env,
    u_int32_t fast_clock, u_int32_t slow_clock);  </pre>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_clockskew()</code> method sets the
         clock skew ratio among replication group members based on the fastest
         and slowest measurements among the group for use with master leases.
         Calling this method is optional; the default values for clock skew
         assume no skew.  The user must also configure leases via the 
         <a class="xref" href="repconfig.html" title="DB_ENV-&gt;rep_set_config()">DB_ENV-&gt;rep_set_config()</a> 
         method. Additionally, the user must also set the master lease timeout
         via the 
         <a class="xref" href="repset_timeout.html" title="DB_ENV-&gt;rep_set_timeout()">DB_ENV-&gt;rep_set_timeout()</a> 
         method. For Base API applications, the user must also set the number of
         sites in the replication group via the 
         <a class="xref" href="repnsites.html" title="DB_ENV-&gt;rep_set_nsites()">DB_ENV-&gt;rep_set_nsites()</a> 
         method.  These methods may be called in any order.  For a description
         of the clock skew values, see 
         <a href="../../programmer_reference/rep_clock_skew.html" class="olink">Clock skew</a>
         in the <em class="citetitle">Berkeley DB Programmer's Reference Guide</em>.  For a description of
         master leases, see 
         <a href="../../programmer_reference/rep_lease.html" class="olink">Master leases</a> in the
         <em class="citetitle">Berkeley DB Programmer's Reference Guide</em>.
    </p>
      <p>
         These arguments can be used to express either raw measurements of a
         clock timing experiment or a percentage across machines.  For example, if
         a group of sites has a 2% variance, then <span class="bold"><strong>fast_clock</strong></span> should be set to 102, and
         <span class="bold"><strong>slow_clock</strong></span> should be set to 100.  Or,
         for a 0.03% difference, you can use 10003 and 10000 respectively.
    </p>
      <p>
         The database environment's replication subsystem may also be
         configured using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. The syntax of
         the entry in that file is a single line with the string
         "rep_set_clockskew", one or more whitespace characters, and the
         clockskew specified in two parts: the fast_clock and the
         slow_clock.  For example, "rep_set_clockskew 102 100". Because the
         <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read when the database environment is opened,
         it will silently overrule configuration done before that time.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_clockskew()</code> method configures a database
         environment, not only operations performed using the specified 
         <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_clockskew()</code> method may not be called after the
         <a class="xref" href="repmgrstart.html" title="DB_ENV-&gt;repmgr_start()">DB_ENV-&gt;repmgr_start()</a>  or
         <a class="xref" href="repstart.html" title="DB_ENV-&gt;rep_start()">DB_ENV-&gt;rep_start()</a> 
         methods are called.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_clockskew()</code> <span>
            <span>
                  method returns a non-zero error value on failure and 0 on success.
            </span>
            
        </span>
    </p>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp54086744"></a>Parameters</h3>
            </div>
          </div>
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        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp54061616"></a>fast_clock</h4>
              </div>
            </div>
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          <p>
                 The value, relative to the <span class="bold"><strong>slow_clock</strong></span>, 
                 of the fastest clock in the group of sites.
             </p>
        </div>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp54076984"></a>slow_clock</h4>
              </div>
            </div>
          </div>
          <p>
                  The value of the slowest clock in the group of sites.
             </p>
        </div>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp54052304"></a>Errors</h3>
            </div>
          </div>
        </div>
        <p>
             The <code class="methodname">DB_ENV-&gt;rep_set_clockskew()</code> <span>
            <span>
                 method may fail and return one of the following non-zero errors:
            </span>
            
        </span>
        </p>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp54097928"></a>EINVAL</h4>
              </div>
            </div>
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          <p>
                If the method was called after replication is started with a
                call to the 
                <a class="xref" href="repmgrstart.html" title="DB_ENV-&gt;repmgr_start()">DB_ENV-&gt;repmgr_start()</a> or the 
                <a class="xref" href="repstart.html" title="DB_ENV-&gt;rep_start()">DB_ENV-&gt;rep_start()</a> method; or if
                an invalid flag value or parameter was specified.
            </p>
        </div>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp54061680"></a>Class</h3>
            </div>
          </div>
        </div>
        <p>
                <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  
            </p>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
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            <div>
              <h3 class="title"><a id="idp54100152"></a>See Also</h3>
            </div>
          </div>
        </div>
        <p>
             <a class="xref" href="rep.html#replist" title="Replication and Related Methods">Replication and Related Methods</a> 
        </p>
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